The subject matter disclosed herein relates to a system and method for rotary machine online monitoring.
Certain gas turbine engines include a turbine having viewing ports configured to facilitate monitoring of various components within the turbine. For example, a pyrometry system may be in optical communication with the viewing ports and configured to measure the temperature of certain components within a hot gas path of the turbine. In addition, an optical monitoring system may be coupled to the viewing ports and configured to capture two-dimensional images of the turbine components. Certain optical monitoring systems are configured to provide online monitoring, i.e., capturing images of the turbine components during operation of the turbine. Such optical monitoring systems may include an objective lens directed toward the turbine components, and configured to relay an image of the components to a detector via an optical connection (e.g., borescope, endoscope, fiberscope, etc.). Unfortunately, because the position and orientation of each viewing port is fixed relative to the turbine casing, certain portions of each turbine component (e.g., turbine blade tip, platform, etc.) may be outside of the field of view.
Furthermore, if the objective lens is configured to provide a narrow field of view, particular regions of the turbine components may be monitored with a high spatial resolution. Conversely, if the objective lens is configured to provide a wide field of view, a significant portion of each component may be monitored, but the spatial resolution will be reduced. Consequently, typical optical monitoring systems may only monitor limited regions of the component with high spatial resolution or larger regions of the component with low spatial resolution.